Data transmission method based on non-access stratum message, base station, and user equipment

Provided are a method of transmitting a non-access stratum (NAS) message, comprising: receiving, from user equipment (UE), a request message for establishing a radio resource control (RRC) connection; and sending, to the UE, an RRC connection establishment response message on a first signalling radio bearer (SRB), wherein the RRC connection establishment response message comprises configuration information for a second SRB, the second SRB is used to transmit a first NAS message, and the configuration information is used to configure the second SRB to support a radio link control unacknowledged mode (RLC UM). Further provided in the present invention are a corresponding base station and user equipment.